var nb_images=4;
	while (nb_images>0 &&  Document.getElementById('mea_'+nb_images)==null )	{
		document.getElementById('bt_mea'+nb_images).style.display = 'none';
		nb_images--;
	}
	if (!nb_images) {
		document.getElementById('nav_promo').style.display = 'none';
		document.getElementById('btn_promo').style.display = 'none';
	}